Speed-regulating mechanism



Sept. 25, 1928.` 1,685,440

H. l.. TANNr-:R

SPEED REGULATI NG MECHANI SM Filed Sept. 14, 1927 F/ 50 l 52 53 gf 1 43 59 INVENTOR jfarr L Tanner BY/Z 994/26 A TTORNE YS l the second member of the train a s s rachis! Sept. 192s. Y

UNITED STATES j 1,685,440' 4PATENT oFFicE.

may L. mman, or nnooxnnr, NEW Yonx, AssxsNon To man msrnmirr ool- Y A i rm, mc., or Lone IsLANn crrY, Naw Yeux, A oonroas'rxon oramw Yonx.

` j armament-me y y Applicants nea september 1'4, m1. smal ira. 219,546.

This invention relates to speed regulating mechanism and is in the nature of an improve- Iment on the apparatus disclosed and claimed p v in the patent to Hannibal C. Ford, lNo.

5 1,577,618, March 23, 1926. Y

According to the disclosure of said patent,

` the speed regulation is attained by employing an epicyclic gear trainto one -member of which the prime mover is connected, while to limit- -ing device, such as an escapement, 1s connected. In order that the speed limitin device may be driven there is connected to t e third member of the gear train a device for applying a constant torque thereto against which the speed limiting device reacts. The arrangement is such that for a particular` speed of the prime mover, as determined by the t characteristics of the a paratus, there will be no movement of the tliird member with respect to the first and second members of the gear train, but if the speed of the prime mover differs from such particular speed there will be arelative movement of the 'third member which is utilized for actuating a contact device for altering the s d of therime mover by a suitable contro system, r example, an electrical system.

In said atent the torque is applied to the third mem r of the gear train by means vof a spring acting on a lever ada ted to bear against a cam connectedto the t ird member but which may move with respect to the lever when there is any movement of this third member due to variations in speed of the lprime mover. Such movement of the cam actuates a partof a contact device to cause a vchange in the speed of the .prime mover through the electrical control system. The

contact device normally short-circuits a resistance in the motor circuit and when the contact is broken the current through the motor circuit is reduced and the'speed of the motor drops. This will cause the third mem" ber of the epicyclic gear train to turn 1n theA opposite direction 'and thereby actuate the contact device to c ause an opposite change 1n the speed of the motor or prime mover. The

f` the prime mover will therefore be l e0 liiely regulated and the movable part of the contact device will be continually loscillatingl to effectl regulation of the prime mover through the electrical control stem. If for any reason the increasing of the prime mover'is not checked by thev control system the third member of the gear without injury to the a paratus, continue to turn with it t e cam against which 'the lever bears and cause successive opening and closing of the contact device.

One of the principal objects of the present lnvention is to provide `novel and advantageous means of'sim le'and inex nsive construction for regulating the s of a prime mover.'

Other objects involve the use 'of novel means for varying the supply of energy to the 'primemoven means forvaryingthe re sistance in acontrol circuitof a prime mover, and novelmeans for preventing damage to the apparatus when the prime mover does not respond regulatory means.

,I According vtothe present invention, the speed regulation may be obtained advantageously by means of a resistance element in a control circuit and means' operated by the third member of the epicyclic gear train for quickly enough tothe action of the varying the resistance of said element to increase or decrease the resistance'in accord-4 ance with variation of the speed of the prime mover Vabove or below the predetermined speed. Means'for limiting the operation of lresistance varying means are provided and this means is so connected with the third member of the gear train that the connection will yield but will tend to maintain thead-` justment of the resistance element until the prime mover responds to the influence of the control system and the third member of the epicyclic direction. v

Al further object of the invention relates tomeans for effecting gradual variation of resistance in a control circuit, thereby pre venting arcing of contacts. I

The particular nature of the invention together withy other objects and advantages thereof will appear more clearly upon con- Sideration of the following description and in whichl the accompanying drawin iagram of an ar- Fig. 1 1s a simplified 'rangement for controlling an electric motor' gear train isturned in the opposite in which an escapement is used in the speed ylimiting device;

` Fig. 2 is a detail viev'partly in section `of a yielding connection between the third member of the gear train and the electric control systennand 4 Fig. 3is a view of a modified form of 'device for varying the resistance in the electrical control system. l

Referring to Fig. 1, 10 represents collectively an epicyclic gear train of the bevel type consistlng of a iirst member or gear 11. a second member or gear 12, and a third member 13 which is in the form` of a pair of gears meshing with gears 11 and 12 and mounted upon a spider 14 attached to a shaft 15 upon -which the first and second gears 11 and 12 respectively are loosely mounted in accordance with the usual construction of this particular type of epicyclic gear train.

The lirst member 11 is provided with a gear 16 meshing with a worm 17 on a shaft 18 connected with ythe prime mover, the speed of which is to be regulated. For purposes of illustration the prime mover has been shown as an electric motor 19 provided with an armature 20 and a shunt lield 21. The motor is supplied with current by mains 22 in one of which is inserted a resistance 23 such as a carbon pilehaving a fixed end plate 26 and a movable end plate 27. By varying the prespallet 33, fork 34, balance wheel 35 and sprin The Shaft 15 of the third member is of the epicyclic gear train has an enlarged end 37 against which a gear or pinion 38 is pressed byrmeans of a helical spring 39 interposed between the pinion 38 and a member or disc 40 on a pin 41 which passes through the spring 39 and the pinion 38 into an opening 42 in the head 37 being secured to the head in any suitable manner as by a pin 43. Meshing withthe pinion 38 is a sector 44 carried by an arm 45 fixed on a shaft 46 which also has fixed thereon an arm 47. Pivoted to the arm 47 is a rod48 passing loosely through a fixed member 49 and also pivoted` to one arm of a lever structure or lever 50 of which the other arm forms with a link 5l a toggle by which pressure may be exerted on the movable plate 27 of the carbon pile 23, by means of a member 52 pivoted to link 51 and mechanically connected with the plate 27 but insulated therefrom by insulating material 53. Mounted on the rod or link 48 is a spring 54 interposed between the member 49 and a collar 55 fixed on the rod .48. The spring 54 urges the rod 48 in' a direction to straighten the toggle including the link 51 and the adjacent arm of the lever 50` and thereby exerts pressure'on the parts connecting the pinion 38 with the movable plate 27, which might result from continuous rotation of shaft 15 in one direction, is prevented by-two stops 56 arranged on opposite sides of the arm 4 5, sli page occurring at the connection between t e pinion 38 and the enlargedend 'of the shaft 15 as soon as the arm 45 strikes one of said stops 56.

In considering the operation of the simpliied form of apparatus shown in Fig. 1, et it be assumed that the conditions are substantially asY indicated in said figure, that is, with the late 27 pressed towards the' fixed plate 26 Ay ymeans including the spring 54 so that the resistance of the carbon pile 23 is such as to permit a flow of sufficient current to drivelthe motor 19 at the desired or at a greater speed. The spring 54 will, acting through the rod 48 and other connections including the pinion 38, apply a torque to the third member 13 of the epicyclic gear trainI so that as the first member 11 is rotated by the motor 19, the third and second members 13 and 12 respectively, will also be rotated to drive the escapement through gears 28 and 29 and pinion 30. If the motor drives the first member faster than the member 12 is driven under control of the escapement, the third member 13 will bevdriven relatively to the second member 12 in a direction to compress the sprin 54, thereby actuating tog 1e 50, 51 and reducing the pressure on the p ate 27 and increasing the resistance of the resistance element or carbon pile 23. This has the effeet of reducing the current through the ar- `mature 20 and of reducing the speed of the motor. As soon as the speed of the motor is lreduced to such an extent that the first member llturns at a slower rate than the second member 12,'the third member will begin to turn 1n the opposite direction and permit the spring 54 to expand and operate the toggle,

50, 51 to increase the pressure on the resistance element 23, thereby decreasing the resistance and causing a greater ilow of current through the armature 20 and an increase of speed of the motor.

The use of a suitably designed toggle structure enables variable pressure on the carbon pile 23 to be obtained with a substantially uniform torque on shaft 15 o differential 10. This eiect is obtained due to the fact that as the pressure on the movable plate 27 of the carbon pile is increased the toggle l50, 51 is straightened and for a given torque on the ,shaft 15 a much greater pressure on the plate .predetermined speed at which it will drive the escapement without any movement of the the carbon pile 23. Excessive movement of i lll') l repeated in sequence continually with the ref third .memberof ther epicyclic gear train n about the axis of its-shaft 15. Also when the resistance is increased'due to excessive speed of the motor, the tendency will be t reduce the speed of themotor below 'said predetermined speed. These operations will be 'sult that the speed of the motor will be maintained substantially constant except for such variations as take place before the change of speed is checked by the reduction or increase of the resistance of the resistance unit or car- -bon pile 23 in the motor circuit.

As illustrated in Fig. 3, the resistance .unit in the motor circuit may be in the form of a rheostat`57 including an arm 58 mounted to vswing abouta pivot 59 and be brought into .contact withA any one of a Aseries-of contacts claim:

f nected tol'an'other member of the gear train, and means for controlling said variable re- Y,

` element. f

` 60, thereby varying the resistance in the motor circuiti The 'arm' may be operatively v connected with the rod or link' 48 of Fig. 1 by means of an arm 61 pivotally connected with said rod 48 and rigidly connected with said arm 58 adjacent said vpivot 59, suitable insulation of the parts being obtained b use of insulating material 62. It will be evident vthat the rheostat shown in'Fig. 3 may be` used in the same eneral manner as the resistance unit 23 of Fig. 1 to control the action of I a prime-mover.

It should be 'understood that ,various cha es in the arrangement of the apparatus and 1n details of construction may be made without departing from the truespirit and scfpe of the invention.

ing thusv described my invention,l I

1. In speed regulating apparatus, a prime mover, an electrical s d control system for said prime mover inc uding a control circuit o, and a variable resistance element in said circuit, saidspeed control system being adapted to control the speed of said prime mover in accordance with the variation ofthe resistance of said resistance element, an epicyclic gear train to one member of which the prime mover'is connected, speed limiting means consistance' element yincluding a pinion having a vyielding connection with a third member of thegear train, a memberv connected with said pinion` for actuation thereby, and a spring associated with the member for mov- 4 ing it to vary the resistance of the resistance .2.Inspeed said prime mover in tem being adapted to control the speed of said prime mover in accordance with the variation.

of the resistance of said resistance element, -vannepicycliegear train to'one member of regulating apparatus, a prime mover, an electricaly speed control system for c uding a control circuit` yand a lpresaure-controlled variable resistance element in said vcirc u`it,.said speed control sys- -which the prime mover is connected, speed limitingmeansV connected to Zanother member 'of the gear, andmeans for varying the pressure on said resistance element includin a toggle acting thereon and means for actuating said toggle including a yieldable4 connection with a third member of the gear train.

' 3. In'speed regulating apparatus, a prime mover, an electrical speed control system for said prime mover including a control circuit and a pressure-controlled variable resistance element in said circuit, said speed control systembeing adapted to control the Speed of ysaid prime mover in accordance with the variatlon of the resistance of sald resistance element,- an epicyclrc gear tram to one member of which the prime mover is connected, speed limiting means connected to another member of the gear,-and means for varymg the pressure on said resistance unit inc uding a toggle, a spring tending to actuate saidv tog- "'gle to vary the pressure, and means actuated by a third member of the gear train for con-' trolling said toggle.

4. In speed regulatingapparatus, a primey a mover, an electrical speed control system for said prime mover including a control circuit and a pressure-controlled variable resistance element in said circuit, said speed control system being adapted to control the speed of v said prime mover in accordance with the variation of the resistance of said resistance element, an epicyclic gear train to one member of which the prime mover is connected, speed limiting means connected to another member `of the gear, and means for varying thel preslsurel on said resistance elementv including a toggle,a'spring tending to actuate said togsistance element in said circuit, said speedy control system being adapted to control the" speed ofwsaid prime mover in accordance with thev variation of the resistance of said resistance element, an epicyclic gear train to one member of A which the prime mover is connected, speed limiting means connectedto anothermemberof the gear, means for varying the `pressureon said resistance unit including a yieldable connection with a third member of the gear train, and means for limiting op- .las

eration of such pressure-varying means. 6l In'speed regulating apparatus, the-combination with an electric motor, a motor cir-` cuit, an epicyclic 'gear train to. onel member `of whichthe prime mover is connected, speed `limit-ing means connected to another member of the gear train, and means for applyin a substantially constant torque to a. thir member of the gear train, of a rheostat, and rheostat-controlling means operable by said third member, the connection between saidA third member and said rheostat-controlling means being yieldable to prevent damage when the prime mover does not respond quickly enough to the action of the speed control.

7. In speed regulating apparatus, a prime mover, an eplcyclic gear train to 4one member of which the prime mover is connected, speed limiting mechanism connected' acting directly on the speed altering means.

'8. In speed regulating apparatus, a prime mover, an epicyclic gear traln to one member of which the prime mover 1s connected,

35 speed limiting mechanism` connected to another member of the gear train, means for altering the speed of the prime mover and including an actuating member movable with varying resist-ance in different parts of its path, and means actuable by a third member of the e icyclic gear train for controlling the speed a tering means and adapted to operate said actuating member with a constant torque on said third member.

9. In speed regulating apparatus, a prime mover, an epicyclic gear train to one member of which the prime mover is connected, speed limiting means connected to another member of the gear train, means for altering the s of the prime mover including acontro ling member against which preure must be, exerted in an increasing or decreasing manner to vary the speed of the prime mover, and means actuable by a'thrd member of the epicyclic gear Atrain and includnga toggle acting on said controlling member and adapted to vary the pressure thereon with a constant torque on said third member.

In testimony whereof Iax my signature.

HARRY L. TANNER. 

